Metabolism of the carcinogenic hydrocarbon benzo(a)pyrene in human fibroblast and epithelial cells. II. Differences in metabolism to water-soluble products and aryl hydrocarbon hydroxylase activity.

Aryl hydrocarbon (benzo(a)pyrene) hydroxylase (AHH) activity and metabolism of benzo(a)pyrene to water-soluble products were measured in cultures of body fibroblasts and kidney epithelial cells from different human embryos. AHH activity at 24 h after treatment with or without benz(a)anthracene was determined in cultures from 23 embryos, and 3 days' accumulated metabolism of benzo(a)pyrene to water soluble products was measured in cultures from 18 embryos. The body fibroblasts from the different embryos could be divided into three groups according to the amount of water-soluble products, but not according to the AHH activity. These three groups were not found by either assay in the cultures of kidney epithelial cells. In both fibroblast and epithelial cells, high metabolism to water-soluble products was not necessarily associated with high AHH activity. The results extend our previous finding (Huberman and Sachs, 1973) of three presumably genetic groups for BP metabolism to water-soluble products in human fibroblast but not in epithelial cells and indicate that this grouping was not found in these cells by measuring AHH activity.